Various systems and approaches have been designed to facilitate communications to the hearing-impaired, including the use of sign language. Sign language can be provided by signers giving a presentation, as well as interpreters who relay information that is spoken during a presentation. Signers and interpreters are practical because they are very portable and do not require sophisticated equipment. Unfortunately, however, because sign language is a visual language, the hearing-impaired can miss important visual material and cues from the presentation when they are focusing on the signer or interpreter.
The foregoing problem is exacerbated in certain settings like museums or planetariums where the referenced objects that are positioned far away from the signer. In such situations, the presentation will be paused, repeatedly, to allow the spectators to focus their attention back and forth between the signer and the referenced objects. Unfortunately, such delays often result in an overall degraded experience and challenging environment for learning.
Some hearing-impaired viewers can benefit from the use of closed captioning for video presentations. However, young children who are unable to read or process the closed captioning do not realize the same benefits. Closed captioning can also be very distracting and undesirable for those that are not hearing-impaired.